It is well recognized that abnormally low levels of potassium chloride in the body may be caused by certain disease states or the administration of certain therapeutic agents, such as, for example, corticosteroids or thiazide-type diuretics. The symptoms of this condition, hypokalemia, include muscular weakness and cardiac disturbances. Treatment of this condition normally comprises replacement of the potassium ion. In view of the fact that therapy with therapeutic agents such as those mentioned above may often be on a prolonged basis, it is often the case that potassium chloride replacement thereapy must be maintained over extended periods of time.
The art is appraised of problems inherent with the administration of potassium chloride. Potassium chloride has been found to be irritating to the gastric mucosa and, therefore, be a potential source of ulceration. This has been shown to be true, for example, with enteric-coated potassium chloride tablets which have caused lesions of the lower bowel over a period of time in all probability due to irritation caused by the concentration of potassium chloride at the sites in the intestinal wall where such tablets dissolve.
There have been numerous attempts to formulate potassium chloride into dosage forms designed to overcome problems such as that described above with varying degrees of success. One approach to the formulation of potassium chloride is to compound it into a liquid formulation. Such a preparation would, for example, be advantageous in that it would be relatively free from the areas of irritation caused by high concentration of potassium chloride at the site of dissolution of a tablet in the stomach or intentinal tract. A second obvious advantage of such liquid preparations would be acceptance by those patients who have difficulty swallowing a tablet.
However, liquid preparations containing potassium chloride can themselves be irritating and, therefore, can cause undesirable effects, such as nausea, diarrhea and gastric upset. The most significant disadvantage of liquid potassium chloride preparations known heretofore is that, regardless of the type of liquid preparation or formulation thereof, such preparations do not have an acceptable taste. It is significant that attempts to date to market a liquid form of potassium chloride have not fared particularly well in comparison with commercial tablets due in the main to the inability of such preparations to mask the salty, objectionable taste of potassium chloride.
The present invention is concerned with a novel water-in-oil emulsion which has been found to efficiently mask the taste of potassium chloride, as well as minimizing the potential irritation of potassium chloride in the gut. The fact that these objectives have been realized utilizing a water-in-oil emulsion is considered unexpected, since water-in-oil emulsions are generally utilized in the health care field only for topical cosmetic preparations, such as cold creams, cleansing creams and the like. Currently, there are no orally administered water-in-oil pharmaceutical products on the market. This may be due to the fact that, in past years, those skilled in the art have generally considered water-in-oil emulsions less stable than oil-in-water emulsions. It has been found, however, in accordance with the present invention that a water-in-oil emulsion can be prepared which effectively masks the objectionable taste of potassium chloride and which has acceptable stability even in the presence of very high electrolyte levels which tend to destabilize most emulsions using conventional emulsifiers.